1. Field of Invention
This invention relates to compounds which promote the release of growth hormone when administered to animals. In another aspect, this invention relates to methods for promoting the release and elevation of growth hormone levels in animals, including humans, by administration of specified growth hormone releasing compounds.
2. Description of Related Art
The elevation of growth hormone (GH) levels in mammals upon administration of GH-releasing compounds can lead to enhanced body weight and to enhanced milk production if sufficiently elevated GH levels occur upon administration. Further, it is known that the elevation of growth hormone levels in mammals can be accomplished by application of known growth hormone releasing agents, such as the naturally occurring growth hormone releasing hormones.
The elevation of growth hormone levels in mammals can also be accomplished by application of growth hormone releasing peptides, some of which have been previously described, for example, in U.S. Pat. No. 4,223,019, U.S. Pat. No. 4,223,020, U.S. Pat. No. 4,223,021, U.S. Pat. No. 4,224,316, U.S. Pat. No. 4,226,857, U.S. Pat. No. 4,228,155, U.S. Pat. No. 4,228,156, U.S. Pat. No. 4,228,157, U.S. Pat. No. 4,228,158, U.S. Pat. No. 4,410,512, U.S. Pat. No. 4,410,513, U.S. Pat. No. 4,411,890, U.S. Pat. No. 4,839,344, and U.S. Pat. No. 5,486,505.
Antibodies to the endogenous growth hormone release inhibitor somatostatin (SRIF) have also been used to cause elevated GH levels. In this latter example, growth hormone levels are elevated by removing the endogenous GH-release inhibitor (SRIF) before it reaches the pituitary, where it inhibits the release of GH.
Each of these methods for promoting the elevation of growth hormone levels involve materials which are expensive to synthesize and/or isolate in sufficient purity for administration to a target animal. Short chain, relatively simple peptides and free amino acids which have the ability to promote the release of growth hormone would be desirable because they could be readily and inexpensively prepared, easily modified chemically and/or physically, as well as easily purified and formulated; and they should have excellent transport properties.
It would be desirable to have short chain peptides and free amino acids which promote the release and elevation of growth hormone levels in the blood of animals, including humans. It would also be useful to be able to use such substances to promote the release and elevation of growth hormone levels in the blood of animals, including humans.